Block-signal system.



U. S. JACKSON.

BLOCK SIGNAL SYSTEM. APPLICATION FILED MAY 12, 914.

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Patented Aug. 29, 1916.

U. S. JACKSON.

BLOCK SIGNAL SYSTEM.

APPLICATION FILED MAY 12, I914.

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BLOCK SIGNAL SYSTEM.

APPLICATION FILED MAY 12. 1914.

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Patented Aug. 29,- 1916.

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U. S. JACKSON.

BLOCK SIGNAL SYSTEM.

APPLICATION men MAY12,19I4.

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Patented Aug. 29, 1916.

m mwa T12 are an 1 URIAH-S. JACKSON, OF LOWELL, MASSACHUSETTS, ASSIGNOR OF ONE-FOURTH TO EDVTARD F. GOWELL, OF BERWICK; MAINE, AND ONE-FOURTH TO WALTER R. TEIBBETTS, OF SOMERSWORTH, NEW HAMPSHIRE.

BLOCK-SIGNAL SYSTEM.

aieaaaa Specification of Letters Patent.

Application filed May 12, 1914. Serial No. 838,399.

T 0 all whom it may concern Be it known that I, URIAH S. JAoKsoN, a citizen of the United States of America, and a resident of Lowell, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Block-Signal Systems, of which the following is a specification.

This invention relates to block signal systems and more particularly to electrically operated block signal systems for railroads.

The object of the invention is to provide a system of the character described which is simple and efiicient and not liable to get out of order.

The present invention contemplates the provision of a block signal system which is free from moving parts to be actuated by the passing trains. This feature is of value as movable parts, such as trip levers and the like, are often rendered inoperative by snow and ice which makes the whole system use less.

Another feature of the invention comprises signals which normally indicate danger and which are held in position to indicate safety by an electric current. In case of failure of the current the-signals at once indicate danger.

A further feature of the invention comprises means for applyingthe brakes on a passing train when the signal indicates danger.

The invention consists in certain novel features of construction and arrangement of parts which will be fully understood by reference to the description of the drawings and to the claims hereinafter given.

Of the drawings: Figure 1 is a diagrammatic view of a track having a block signal system in accordance with the present invention. Fig. 2 is a diagrammatic view showing the crossing of the tracks. Fig. 3 is a diagrammatic view of a switch. Fig. 1 is a diagrammatic view of the brake applying mechanism preferably carried on each locomotive. Fig. 5 is an elevation shown partly in section of a signal station or semaphore, and Fig. 6 is a section on the line 66 of Fig. 5.

Similar characters designate like parts throughout the several figures of the drawings.

In the drawings, 10 represents a railroad track divided into blocks 10 10", 10 10 etc., by insulating sections 11 on the rails. Each block is provided with a signal station or semaphore shown diagrammatically at 12*, 12, etc. The semaphore is shown more in detail in Fig. 5. A semaphore arm 13 is mounted to swing about apivot 14 mounted on the top of'a post 15. The short end of the arm is provided with a weight 16 which holds the arm normally in a horizontal position with the long end of the arm extended to indicate danger. The arm may be provided with a red lens 17 which, when the arm is in the horizontal position, is in front of a lantern 18. A stop 19 is provided to hold the arm horizontal. The long end of the armis connected bya rod 20 to mechanism adapted to turn the arm toward a vertical position, as shown in dotted lines, to indicate safety.

The means for actuating the rod 20 may comprise an electric motor 21 having a shaft 22 on which is mounted a pinion 23. The pinion 23 is in mesh with a gear 24 mounted on a stud 25. The lower end of the rod 20 embraces a bolt 26 eccentricallv mounted in the gear 2 1. fhen there is no current supplied to' the motor the weight 16 turns the gear 24 so that the arm 13 occupies a horizontal position. When current is supplied to the motor the gear24 is turned in the direction of the arrow until the arm engages a stop 27 in which position the arm is held by the tendencv of the gear 24 to continue its rotation. It will be observed that the arm engages the stop before the gear has turned enough to oring the bolt 26 diametricallv oppositethe rod 20'so that the rotation of the motor isarrested. Current is normally supplied to the motor 21 by a battery 28 carried in the base 29 of the semaphore. The battery is connected with the motor by wires 30 and 31. Each side of-the battery is connected bywires 32 and 33 -with contact blocks 34 and35 of an electrically actuated switch 36. The movable member 37 of the switch is constructed to connect the blocks 34 and 35 when it is desired to indicate danger. By connecting the blocks the battery 28 is short-circuited so that no current will pass to the motor 21 which thereby permits the arm 13 to assume the danger position. The member 37 also connects contact blocks 38, and 39 which are connectedby wiregO V netized by a current passing through wires 46 and 47. The wire 46 is connected by a wire 48 with a contact block of a second electrically actuated switch 49. The wire 47 is connected with the other contact block of the switch and then extended to such outside connections as will be hereinafter described. It is apparent that when the movable member 50 engag'es the contact blocks under the action of a spring 51 the'first or primary switch 36 will be short-circuited so that the electro-magnets 45 will be demagnetized. W'hen current is cut off from the magnets 45 they will cease to hold the movable member 37 away from its coacting contact blocks and the member will then move into the position shown in Fig. 5 short circuiting the motor 21 and electrically connecting the wires 40 and 41.

The secondary switch 49 is normally held inoperative by electro-magnets 52 which are energized by current from a circuit including the wires 53 and 54 which extend outside the base 29. It is apparent that when the switches 36 and 49 are both held in open position by the respective magnets the .switch 36 may be actuated by cutting oii'the supply of current through the wires 46 and 47 or by cutting off the supply of current through the wires 53 and 54 which will actuate the secondary switch 49 thereby short-circuiting the magnets 45 of the switch 36.

Referring now to Fig. 1 and to the block 10 and its semaphore 12 the connection of the semaphore with the track will be explained. The wire 47 is connected with one rail of the adjacent block 10. The. wire 46 runs parallel with the track and enters the semaphore 12 as the wire 53 which leads to the magnet of the secondary switch 49. Passing from the magnets as the wire 54, connection is made with the other rail of the block 10. Thus in effect the wire 46 is connected directly to one rail of the block and the wire 47 to the other. A battery 60 is connected between the rails so that the secondary switch 49 of the semaphore 12 and the primary switch 36 of the semaphore 12 are supplied with current and normally held open. With these switches open the arm 13 of the semaphore 12 is held in safe position as has been described, and the secondary switch 49 of the semaphore 12 is held open so as not to short-circuit the primary switch 36 of that semaphore. The

- semaphore 12 and its connection with the block 10 and the semaphore 12 constitute a unit in the signal actuating system This unit is duplicated at 12 and 12, the semaphores being shown for convenience in illustration on alternate sides of the track.

A train is indicated on the section 10 by the shaft 61 and the wheels 62, which may be assumed to be the driving wheels of an engine. A train on the block 10 sets danger signals on the two adjacent blocks at 12 and 12. This is done by short-circuiting the battery 60 through the wheels and shaft of the engine so that no current flows through the wires 47, 46, 53, and 54. This causes the primary switch 36 of the semaphore 12 to be closed and the secondary switch 49 of the semaphore 12' to be. closed. Closing the secondary switch of the semaphore 12 short-circuits the primary switch of this semaphore so that these two stations indicate danger and warn any train approaching from the front or rear block. The same mechanism which sets the semaphore for danger causes the brakes to be applied to a train which may attempt to pass the danger signals. The mechanism for applying the brakes is shown in Fig. 4.

The air brakes of the train are indicated at 68. The brakes are connected by a pipe 69 with the controlling valve 70. The valve 70 is provided with an actuating lever 71 which is held in position to render the brakes inoperative by a latch 72. The. lever 71 is acted upon by a spring 73 which tends to move the lever into the position shown in dotted lines which applies the brakes. The latch 72 is also acted upon by a spring 74 which tends to lift the latch from the lever 71 so that the spring 73 may act to apply the brakes. The latch 72 is held in engagement with the lever 71 by an electromagnet 75, which is connected by wires 76 and 77 with a battery 78. The wire 76 is connected by a wire 79 with a brush 80 bearing upon a ring 81 mounted on the shaft 61. The wire 77 is connected by a. wire 32 with brushes 83 hearing on rings 84 mounted inside of the wheels 62. The rings 84 are separated from the wheels 62 by insulation 85. It is apparent that if the ring 84: and one of the wheels 62 is connected the battery 78 will be short-circuited thereby cutting off the current applied to the magnet which; will allow the spring 74 to lift the latch 72 from the lever 71 so that the brakes will be applied by the action of the spring 73. The wheel 62 and the ring 84 are connected when the ring 84 engages the contact plate 42 when the semaphore indicates danger, as at this time the wires 40 and 41 leading respectively from the rail and the contact plate. are connected by the movable member 87 of the primary switch 36. By this construction the brakes are applied to a train which attempts to run by a danger signal.

In order that it may be possible for the engineer to run by a danger signal in case 1,196,242 l It of emergency, a switch 86 is provided in the wire 79 so that short-circuiting of the battery may be prevented. When the lever 71 is moved into dotted lines position to apply the brakes a connection is made between the contact blocks 87 and 88 which completes the circuit through a wire 89 which connects a battery 90 with a bell 91.

The general principle of the block system set forthin the description of the unit employed for a straight single track may be adapted for use with the variousvdetails of track structure such as crossings, drawbridges, switches, etc. A suitable connection for use with a crossing of two tracks is shown in Fig. 2. In this construction the secondary switches l9 of the four semaphores adjacent the crossing are connected in series by a wire 96 the opposite ends of which connect with terminal plates 97 A battery 98 is connected between the terminal plates. Each terminal plate is connected by wires 99 with the diagonally opposite rails of the two tracks at the point of crossing. Assuming that a train A enters the block adjacent the crossing, the battery 98 will be short-circuited so that no current will be supplied to the secondary switches 49. This will set the danger signals on the semaphores 1%, 12, 1%, and 12 which will warn and set the brakes on any other train attempting to enter the blocks adjacent to the crossing until after the train A shall have passed from said blocks. A second train approaching, as indicated at B would be warned by the danger signals on the semaphore 12 and the brakes would be applied on the train B when it passed over the contact plate 42 of the semaphore 12 The train B would also set the danger signal behind it at the semaphore 12.

Fig. 3 shows the present invention adapted for use with a switch connecting a branch track. The block 10*, which includes the movable track 100 of the switch, has one rail connected to the wire 54 and the other rail to the wire 47. The battery is connected between the rails so that the block is connected with the semaphores 12 and 12 in} exactly the same way that has been described with reference to a straight track. The free ends of the movable tracks 100 are connected with the fixed tracks of the block by a flexible connection such as cables 101. When a train enters the block 10 the battery 60 is short-circuited and the semaphores are actuated in the usual manner. In order that the semaphores may be set at danger when the switch is open provision is made for short-circuiting the battery by the move ment of the switch. The switch is moved by a lever 102 connected with a bar 103 on which the movable tracks 100 are pivotally mounted. The bar 103 carries an insulated finger 1041E which engages a spring switch 105, the two members of which are connectedwith the opposite sides of the battery 60 by wires 106. By this construction the movement of the switch acts through the finger 104; to close the switch 105 and shortcircuitthe battery 60 which sets danger signals on the blocks adjacent the switch block 10 It is apparent that anyone skilled in the art to which this invention relates will be able to adapt the construction set forth to the various needs of a railroad and therefore it is unnecessary to describe the connections for all the elements of a railroad track;

It is to be understood that the invention is not limited to the exact structure and arrangements of parts shown and described as these are capable of wide variation without departing from the spirit of the invention as defined in the appended claims.

Having thus described my invention, I claim:

1. A block signal system comprising a signal held in position to indicate safety by an electric current, a switch to short circuit said current, an electro-magnet to prevent said switch from short circuiting the current, a battery connected between the rails of a block, connections between the rails of the block and the electro-magnet, a second switch to short circuit said electro-magnet, a second electro-magnet to prevent the second switch from short circuiting the first electro-magnet, and connections from the rails of another block to the second electromagnet.

2. A block signal system for the crossing of two tracks, comprising a battery connected between the rails of the blocks adjacent the crossing and adapted to be short-circuited by a train in said blocks; and semaphores on each side of the crossing held in position to indicate safety by an electric current, and having a switch for short-circuiting said electric current, an electro-mag net to hold said switch in inoperative con dition, and a switch for short-circuiting said electro-magnet and a magnet energized from said battery for holding the last named switch in inoperative condition.

3. A block signal system comprising a signal held in position to indicate safety by an electric current, a switch for short-circuiting said current, an electro-magnet connected between the rails of a block to hold the switch in inoperative position, a battery connected between the rails of said block, and arranged to be short-circuited when a train enters the block, a movable section of track in the block, and means for short-circuiting the battery when the movable section of track is out of alinement with the block.

4:. A block signal system comprising a battery connected between the rails of each block, connections between the rails and a erative from a distant block I safety, a movable section of track in the copies of this patent may be obtained for five cents each, by addressing the block, flexible connections between the movable tracks and the rest of the block, means for short-circuiting the battery when the movable section of track is moved from normal position, and means for short-circuiting the battery when a train enters an adjacent block.

Signed by me at 4 Post Oflice Sq., Boston, Mass, this 7th day of May, 1914:.

URIAH S. JACKSON.

Witnesses:

WALTER E. LoMBAm), NATHAN C. LOMBARD.

Commissioner of Patents,

Washington, D. C. 

